As an exploratory experiment on syntheses of sorigenins (I), 1-methoxy-3-hydroxymethyl-2-naphthoic acid γ-lactone (VIII) and 3-hydroxymethyl-4-methoxy-2-naphthoic acid γ-lactone (XV) were synthesized. Compound (VIII) was prepared from 3-hydroxymethyl-3, 4-dihydro-1 (2H)-naphthalenone (IV) as shown in Chart 1. Compound (XV) was prepared through reduction of 3-ethoxycarbonyl-4-hydroxy-2-naphthoic acid (XVIII) and its methyl ether (XX) with lithium aluminium hydride. Reductions of 1-methoxy-2, 3-naphthalenedicarboxylic anhydride (XIV) and of the halfester prepared by alcoholysis of (XIV) with lithium aluminium hydride were found to give a mixture of (VIII) and (XV).
作为对合成索瑞
金(I)的一项探索性实验,合成了1-甲氧基-3-羟甲基-2-
萘酸γ-内酯(VIII)和3-羟甲基-4-甲氧基-2-
萘酸γ-内酯(XV)。化合物(VIII)是从3-羟甲基-3, 4-二氢-1(2H)-
萘酮(IV)合成的,如图1所示。化合物(XV)则是通过用
锂铝
氢化物还原3-乙氧基羧基-
4-羟基-2-
萘酸(XVIII)及其甲基醚(XX)得到的。发现用
锂铝
氢化物还原1-甲氧基-2, 3-
萘二酸酐(XIV)及其醇解生成的半酯,能够得到(VIII)和(XV)的混合物。